Primary patency is defined as the interval from balloon angioplasty until the next access thrombosis or repeated intervention to maintain access function, or until access abandonment if no interval intervention. It ends with treatment of a lesion anywhere within the access circuit, from the arterial inflow to the superior vena cava-right atrial junction.

Primary assisted patency is defined as the interval from balloon angioplasty until access thrombosis or a surgical intervention that excludes the treated lesion from the access circuit. Examples include percutaneous treatments of either restenosis/occlusion of the previously treated lesion or a new arterial or venous outflow stenosis/occlusion (excluding access thrombosis). It ends with percutaneous thrombolysis/thrombectomy or simple surgical thrombectomy.

Secondary patency is defined as the interval after balloon angioplasty until the access is surgically declotted, revised or abandoned because of inability to treat the original lesion, choice of surgeon, transplant, loss to follow-up, etc. Examples include thrombolysis and percutaneous thrombectomy, as well as multiple repetitive treatments.

The conventional balloon is used and the diameter of the balloon should be the same or oversized by 1mm the diameter of the reference vessel.

An inflation device with a pressure gauge is used to inflate up to manufacturers' stated burst pressure. The duration of balloon inflation will be 2 minutes.

At the end of the first angioplasty, an AVFistulogram/AVGraftogram will be obtained to document results. If there is residual stenosis of >30%, a repeat angioplasty using the same balloon or another appropriately oversized balloon by 1mm will be used for an additional 2 minutes. A final angiogram will be obtained for documentation.

Device: Conventional PTA

Use of conventional balloon for angioplasty only

Other Name: REEF angioplasty balloon (Manufacturer Medtronic)

Experimental: Drug Eluting Balloon (DEB)

Treatment arm 2 - Conventional Balloon with DEB

A Conventional balloon is used to pre-dilate the target lesion. The DEB of a similar diameter to the conventional balloon used is then inflated across the stenosis. An inflation device with a pressure gauge is used to inflate up to manufacturers' stated burst pressure. The duration of balloon inflation will be 1 minute. A final angiogram will be obtained for documentation. The drug coated on the DEB is Paclitaxel.

Device: Drug Eluting Balloon (DEB)

Use of DEB after conventional balloon angioplasty

Other Name: IN.PACT ADMIRAL Paclitaxel-eluting Balloon (Medtronic)

Detailed Description:

Introduction:

Neointimal hyperplasia is the main cause of hemodialysis access [arterio-venous fistula (AVF) or graft (AVG)] dysfunction and thrombosis. Although endovascular techniques like percutaneous transluminal angioplasty (PTA), catheter directed thrombolysis, mechanical thrombectomy or bare metal stenting, may salvage the access, long term patency remains dismal due to recurrent stenosis from neointimal hyperplasia.

Drug Eluting Balloon (DEB) is effective in inhibiting neointimal hyperplasia for treatment of coronary in-stent restenosis since 2006 and more recently in femoropopliteal arteries, reducing restenosis rates and prolonging patency.

Specific Aim:

To determine the efficacy of DEB in reducing restenosis rates and prolonging the patency of AVFs/AVGs compared to PTA.

Hypothesis:

DEB is superior to PTA in reducing late luminal loss and restenosis rates, while prolonging primary and secondary patencies.

Methodology:

Prospective, randomized clinical trial with study population comprising of patients with dysfunctional AVFs/AVGs due to underlying stenoses. The patients will be randomized to receive either DEB or PTA.

The 6-month late luminal loss will be primary endpoint. The secondary endpoints of restenosis rate, primary and secondary patencies, will also be determined.

Any strategy that reduces access failure or prolonging access lifespan will be beneficial. If DEB is proven to be superior to PTA, there will be a paradigm shift in management of hemodialysis access failures from restenosis - similar to how DEB has changed practice in managing coronary artery in-stent restenosis.

Eligibility

Ages Eligible for Study:

21 Years and older

Genders Eligible for Study:

Both

Accepts Healthy Volunteers:

No

Criteria

Inclusion Criteria:

Upper limb or groin AVF/AVG

The AVF/AVG is > 3 months old.

Native vessel measures between 4 to 7 mm diameter (corresponding to the sizes of available DEBs).

The fistula or graft must not be thrombosed.

Able to cross with guide wire

Platelet count >50,000/l (platelet infusion if <100,000/l)

PT/PTT not more than 3 seconds above normal (FFP infusion for abnormal PT/PTT)

Evidence of systemic infection or a local infection associated with the fistula or graft.

The patient is < 21 years of age.

The patient is pregnant.

Patient is enrolled in another investigational study

Patient has comorbid conditions that may limit their ability to comply with the follow-up requirement.

Life expectancy < 6 months

Contacts and Locations

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study.
To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below.
For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01544907